package circulate_algorithm_study;

import java.util.Scanner;

public class Count_Species {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int k = sc.nextInt(), count = 0;
        for (int i = 1; i < k + 1; i++) {
            for (int j = 1; j < i + 1; j++) {


            }
            int i1 = i * i;
            count += i1;
        }
        System.out.println(count);

    }
}
